Single-edge razor blade sickle



Feb. 26, 1 952 A. LARSON 2,587,336

SINGLE-EDGE RAZOR BLADE SICKLE Filed June 25. 1949 ATTORN EV Patented Feb. 26, 1952 UNITED STATES PATENT OFFICE 2,587,336 SINGLE-EDGE RAZOR BLADE SIOKLE A rvid Larson, East Meadow, N. Y. 7 Application June 25 1949, Serial No. 101,316

1 Claim. l

This invention relates to grass cutters ofv the manually operated hook-shaped or sickle type, and in particular a hand sickle having a cutter bar with an offset handle and in which razor blades of the single edge type are clamped between a base and a cover plate to provide the cutting edge of the sickle. i

The purpose of this invention is to provide an improved method of mounting safety razor blades with backs and with a single cutting edge in a cutter bar of a hand sickle whereby the blades are rigidly held and may readily be removed.

Different methods have been provided for mounting various kinds of safety razor blades in handles and knife blades but it is difiicult to clamp blades having enlarged backs between two elements of a cutter bar without danger of the blades working loose. With this thought in mind this invention contemplates a cutter bar base having slots or recesses in the upper surface for receiving the enlarged backs of razor blades and projections on the said upper surface positioned to coact with the recesses for positioning blades on the base with the cutting edges thereof extended slightly over the leading edge of the base.

The object of this invention is, therefore, to provide means for forming a base of a cutter bar of a hand sickle so that single edge safety razor blades with enlarged backs may be rigidly clamped in the cutter bar.

Another object of the invention is to provide means for clamping safety razor blades with backs in a cutter bar of a hand sickle without changing the blades.

A further object of the invention is to provide a cutter bar for single edge safety razor blades and blades with backs which is of a simple and economical construction.

With these and other objects and advantages in view the invention embodies a hook-shape cutter bar having a base with razor blade back receiving recesses therein and projections there-.

on and having an offset handle, and a cover plate secured to the base with screws.

Other features and advantages of the invention will appear from the following description taken in connection with the drawings, wherein:

Figure 1 is a plan view of the sickle showing the parts assembled.

Figure 2 is a detail showing the parts on an enlarged scale illustrating the method of clamping the blades on the base with parts of the base broken away and with some of the blades removed.

Figure 3 i a detail illustratingv the formation of the recesses and projections of the base of the. cutter bar.

Figure 4 is a detail showing the under surface of the cover plate with the ends of the plate brokenaway. a

Figure 5 is a typical cro s section through the cutter bar showing a modification wherein the cover plate is secured to the base by countersunk head screws with thumb nuts.

Figure 6 is a detail showing a side view of the handle end of the cutter bar with part of the base broken away and with the cover omitted.

Referring now to the drawings wherein like reference characters denote corresponding parts the single cutting edge cutter bar for hand sickles of this invention includes a base l0 having a handle ll integral therewith and offset therefrom, a cover plate l2, and blades l3 having reinforcing bars forming backs 14.

The base of the sickle is hook-shaped and the upper surface thereof is formed with spaced pockets or longitudinally disposed elongated recesses l5 which are positioned to receive the backs or bars Id of the cutting blades, as shown in Figures 2 and 5. The upper surface of the base is also provided with transversely disposed projections or lugs [B which are positioned to extend into centrally positioned transversely disposed slots I! in the blades. The projections are positioned midway of the lengths of the recesses l5 and between the recesses and leading edge of the base 10. The base is also provided with screw openings I8 that are positioned between the recesses and ends of blades held in the recesses.

The cover plate I2 is formed with a continuous recess IS in the under surface and also notches 20 in a blade clamping lip 2| on the forward edge, and the notches are positioned to 00-- act with the projections Hi to positively clamp the blades in cutting positions on the cutter bar base.

The cover plate is secured to the base by thumb nuts 22 on screws 23 which, in the design shown,

. have countersunk heads 24. The recess in the under surface of the base provide a springy action whereby the nuts are held in tension on the screws so that look washers and the like are not required.

With the parts arranged in this manner the blades are positively locked in the cutter bar and may readily be removed and replaced by loosening the thumb nuts, as shown in Figure 5. or the screws 25 shown in Figure 1.

It will be understood that modifications may be made in the design and. arrangement of the parts without departing from the spirit of the invention.

What is claimed is:

In a hand sickle, the combination which comprises an arcuate base having an inner edge on one radius and an outer edge described on a larger radius, said base having a handle at one end and said handle positioned in a plane spaced from the plane of the base, said base also having spaced elongated longitudinally disposed recesses, rectangular-shaped in plan, in a face thereof and transversely disposed elongated lugs with arcuate ends extended from said face and.

positioned between said recesses and the inner edge of the base and midway between the ends of the recesses, blades, rectangular-shape in.

plan, and having sharp edges on one side and reinforcing bars on both surfaces of the opposite sides positioned substantially end to end on said face of the base and with the reinforcing bars on one of the surfaces thereof in the said recesses of the base, said blades also having transversely disposed slots therein and said slots positioned to receive the elongated transversely disposed lugs of the base whereby the blades are located in cutting positions in the sickle, a cover plate having a longitudinally disposed recess in the under surface, said recess having a plurality of spaced notches adapted to receive said lugs and cooperate therewith to clamp the blades in cutting position, said cover being positioned on the base with one edge resting upon the base and the opposite edge in engagement with said blades, and screws with thumb nuts thereon extended through said base and cover plate for clamping the cover plate against the base at one side and against the blades at the opposite side, said screws positioned between ends of the blades. ARVID LARSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

